UNMC, Canadian researchers make discovery may render Staphylococcus harmless

Like a switch that turns on a light, the mechanism that turns Staphylococcus aureus bacteria from harmless to deadly has been identified by Canadian scientists with the aid of University of Nebraska Medical Center researchers in Omaha.

In an international collaboration, Paul Dunman, Ph.D., associate professor, pathology/microbiology, and his post doctoral trainee, Christelle Roux, Ph.D., provided key data on the breadth of activity that two molecules have to switch staph into an infectious organism.

Staphylococcus aureus, also referred to as “staph,” kills about 100,000 Americans each year and would be harmless but for the action of the regulating molecules, or peptides.

The major breakthrough was reported by researchers at UNMC, McMaster University in Hamilton, Ontario, and the University of Western Ontario, in a recent edition of Science Express, the online version of the journal that promotes articles with significant findings.

“I’ve studied virulence factors for 10 years and have never seen anything of this magnitude,” said Dr. Dunman, a member of UNMC’s newly formed Center for Staphylococcal Research. “These small peptides that allow staph to become infectious will be good targets for new drug discovery.”

The next step will be to study the mechanism to discover how the molecule regulates the virulence factors and to identify compounds that will inhibit the peptide, Dr. Dunman said.

The next phase of the study will be conducted by Nathan Magarvey, Ph.D., assistant professor, biochemistry, biomedical sciences and chemistry, McMaster University. The principal investigator of this study, Dr. Magarvey first spoke with Dr. Dunman about collaborating on this project 18 months ago.

“Paul is a recognized world leader in microarray technology. He’s a rock star,” Dr. Magarvey said. “The first antibiotics effective against staph are made from molecules of the same general class as these staph peptides.”

Staph is present on the skin or in the nose of healthy people and:

Causes 1.7 million infections annually in the United States;

Is the culprit of many minor and, thus, unreported skin infections; and

Has been a leading cause of hospital infections worldwide.

Ken Bayles, Ph.D., professor, pathology and microbiology, and director of UNMC’s Staphylococcal Research Center, said the discovery is surprising. “With all the research that’s been done on staph, there are still gems to be found.”